Climate shocks, crop losses and health risks in Africa ^{CEFR B1}

Climate shocks are altering ecosystems across Africa and creating new pathways for disease. In Bazua, in Ghana's Upper East region, farmer Martin Ariku describes a season of failed expectations. For more than 20 years he supplied improved seeds to smallholder farmers. This year drought came early, and then intense short rainstorms drowned surviving plants. Yields fell to as low as five 100-kilogram bags per acre for maize, rice, cowpea, soybean and sorghum, compared with the usual 15. Even a sorghum variety introduced by SNV Ghana failed to survive the rapid swings.

Crop losses also affect future planting because grain that fails to mature cannot be used as seed. Warmer nights and changing rainfall have helped pests such as Fall Armyworm to spread. A CABI survey found that almost all farmers questioned in Ghana and Zambia said their maize crops had been infected; farmers reported large average losses. CABI also estimates major annual maize losses in both countries.

Scientists warn that higher temperatures speed pest metabolism and reproduction, letting pests expand their range. Shauna Richards at the International Livestock Research Institute says new pools of stagnant water from heavier rains create breeding grounds for mosquitoes. Floods can mix sewage with drinking water and raise the risk of cholera. In the Ashanti region some families report hotter nights and more malaria, and new mosquito species have appeared in cities. Public-health experts say clinics need stronger buildings, reliable electricity and better vaccine systems as the climate crisis progresses.